Ron bought 8 pencils and 2 erasers for $1.66. sarah bought 12 pencils and 5 erasers for $3.19. what is the cost for 1 pencil and 1 eraser?

P=price of 1 pencil
e=price of 1 eraser

1.66=8p+2e
divide by 2 for simplification
0.83=4p+e

3.19=12p+5e

0.83=4p+e
multiply by -5 and add to obht eration

-4.15=-20p-5e
3.19=12p+5e +
-0.96=-8p

divide by -8
0.12=p
sub back

0.83=4p+e
0.83=4(0.12)+e
0.83=0.48+e
minus 0.48 both sides
0.35=e

1e+1p=0.12+0.35=0.47

cosst is $0.47

The population here is the entire school body.

The population is the main group the survey is about. In this case, it is about the school. However, his sample was just the football team.